CBS is continuing to cast its core group of characters for Supergirl, with former Ally McBeal star Calista Flockhart coming aboard to play Cat Grant. She will star opposite Melissa Benoist as Kara Zor-El, playing the former Kryptonian's boss at CatCo. Greg Berlanti, the man behind The CW's Arrow and The Flash, is executive producing.

The Supergirl pilot is based on the popular DC Comics character, who just happens to be Superman's cousin. The story follows Kara, who has been hiding her powers from the world. At the age of 24, she decides to embrace her superhuman abilities to become the hero she was always destined to be. Kara also works as an assistant to Cat Grant, a self-made media conglomerate and founder of CatCo.

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Calista Flockhart's Cat will be a former reporter who has built her own company into a global entity. This will be the actress' first major role since leaving ABC's Brothers & Sisters in 2011. Greg Berlanti was also a producer on that series, which played a large part in getting Calista Flockhart to sign on.